A Home evolved NodeB (HeNB) is a small base station, which is mainly used at home and in small public places. Because a coverage area is small, lower power is used to send information. The HeNB may also participate in Multimedia Broadcast multicast service Single Frequency Network (MBSFN) transmission of an outdoor evolved NodeB (eNB), so as to transmit a Multimedia Broadcast Multicast Service (MBMS) in the HeNB.
In an MBSFN transmitting manner, a plurality of cells is pre-configured to form an MBSFN combination area, and a plurality of eNBs in the combination area uses the same radio resource to transmit the MBMS, that is, the same service data is sent to all User Equipments (UE) in the combination area at the same time, for the UE, signals from the eNBs are like being from the same eNB, and the combination of the signals equals to the strengthening of the signal.
The MBMS and other services are transmitted in a time division manner, that is, some sub-frames are reserved from all cells inside the combination area to transmit the MBMS, the reserved sub-frames of each cell to transmit the MBMS are the same. The sub-frames are called MBSFN sub-frames and other sub-frames are arranged by each cell to transmit other services, and are called common sub-frames. In the prior art, the data packets of each service are divided into several synchronization sequences. A gateway transmits the data packet to each eNB in the combination area according to the synchronization sequences and transmits, after each synchronization sequence, a synchronization control packet. The synchronization control packet includes size information of each data packet transmitted according to the synchronization sequence. The eNB performs segmentation concatenation process on the data packet in the synchronization sequence after receiving the synchronization control packet. If a packet is lost, the eNB empties a transmission position occupied by the lost packet according to information in the synchronization control packet, and finally generates a data block transmitted on an air interface. The eNB transmits the data blocks in sequence in each pre-distributed MBSFN sub-frame. In the existing protocol, a plurality of MBMS services may be multiplexed in one Multicast Channel (MCH).
The currently proposed technical solution of transmitting the MBMS in the HeNB is to transmit data packets of all MBMS services to each HeNB in the combination area through the gateway, and transmit, after each synchronization sequence of each service, one synchronization control packet, and after receiving the synchronization control packet, each HeNB performs segmentation concatenation operation on the data packet in the synchronization sequence, and then sends, according to the service requirement of the subjacent UE thereof and in the corresponding MBSFN sub-frames, a service required by the UE to the subjacent UE. The services not required are not sent, and those MBSFN sub-frames in which no service needs to be sent may keep silent.
In the prior art, in order to ensure MBSFN transmission, the gateway transmits the data packets of all services mapped onto the same transmission channel to each HeNB in the combination area. Therefore, the load of a transmission link between the gateway and the HeNB is too large.